/* 背景 */
body {
    /* 渐变背景 */
    background: linear-gradient(180deg,#20b2aa,#edfffe);
    /* 溢出隐藏 */
    /* overflow: hidden;*/
}
html, body {
    height: 100%;
    margin: 0;
    padding: 0;
}
.square li{
    position: absolute;
    border: 1px solid #fff;
    background-color: #fff;
    width: 30px;
    height: 30px;
    list-style: none;
    opacity: 0;
    z-index: -1;
}
.circle li{
    position: absolute;
    border: 1px solid #fff;
    background-color: #fff;
    width: 30px;
    height: 30px;
    list-style: none;
    opacity: 0;
    z-index: -1;
}
.square li{
    top: 40vh;
    left: 55vw;
	border-radius: 50%;
    /* 执行动画：动画名 时长 线性的 无限次播放 */
    animation: square 8s linear infinite;
}
.square li:nth-child(2){
    top: 80vh;
    left: 10vw;
    /* 设置动画延迟时间 */
    animation-delay: 2s;
}
.square li:nth-child(3){
    top: 80vh;
    left: 85vw;
    /* 设置动画延迟时间 */
    animation-delay: 4s;
}
.square li:nth-child(4){
    top: 10vh;
    left: 70vw;
    /* 设置动画延迟时间 */
    animation-delay: 6s;
}
.square li:nth-child(5){
    top: 10vh;
    left: 10vw;
    /* 设置动画延迟时间 */
    animation-delay: 8s;
}
.circle li{
    bottom: 0;
    left: 15vw;
    /* 执行动画 */
    animation: circle 8s linear infinite;
}
.circle li:nth-child(2){
    left: 35vw;
    /* 设置动画延迟时间 */
    animation-delay: 2s;
}
.circle li:nth-child(3){
    left: 55vw;
    /* 设置动画延迟时间 */
    animation-delay: 6s;
}
.circle li:nth-child(4){
    left: 75vw;
    /* 设置动画延迟时间 */
    animation-delay: 4s;
}
.circle li:nth-child(5){
    left: 90vw;
    /* 设置动画延迟时间 */
    animation-delay: 8s;
}

/* 定义动画 */
@keyframes square {
    0%{
        transform: scale(0) rotateY(0deg);
        opacity: 1;
    }
    100%{
        transform: scale(5) rotateY(1000deg);
        opacity: 0;
    }
}
@keyframes circle {
    0%{
        transform: scale(0) rotateY(0deg);
        opacity: 1;
        bottom: 0;
        border-radius: 0;
    }
    100%{
        transform: scale(5) rotateY(1000deg);
        opacity: 0;
        bottom: 90vh;
        border-radius: 50%;
    }
}